public class ABC {
}
class Sum {
    public void sum(int x, int y) {
        System.out.println(x + y);
    }

    public void sum(double x, double y) {
        System.out.println(x + y);
    }

    public void sum(int x) {
        int y = 0;
        for (int i = 1; i <= x; i++) {
            y += i;
        }
        System.out.println(y);
    }

    public void sum(String x, String y) {
        System.out.println(x + y);

    }
}